Jones, who retired from baseball in 2012 after a 19-year career in Atlanta, reportedly tweeted Friday: “So the FBI comes out and confirms that Sandy Hook was a hoax! Where’s the outrage? What else are we being lied to about? Waco? JFK? Pff … ”

The tweet was deleted, but not before it was apparently captured by several Twitter users. Jones’ account has 446,000 followers.

Jones apologized Saturdayin two tweets, saying he had “heard something from someone which I thought to be credible and tweeted w/out researching.” Jones also said, “It was irresponsible of me to do that and will not happen again. Please accept my heartfelt apology to those who were hurt or offended.” Click here to see the apology.

The school shooting occurred Dec. 14, 2012, in Newtown, Connecticut, where 20-year-old Adam Lanza killed 20 children and six adults before killing himself. Lanza also fatally shot his mother before going on the rampage.